Linvi Charles wrote: > Can a diphthong be formed without a semivowel? Wouldn't the vowel cluster > always be more than 1 syllable if both vowels are articulated equally? It depends on what you consider a semivowel -- I've had languages with diphthongs like /eo/ and /oe/, which could be treated as [eo_^], [oe_^], etc. You wouldn't call [o_^], [e_^] approximants, but maybe semivowels would be an appropriate term. You could use other phonological properties to tell if both elements of the diphthong are part of the same syllable e.g. if stress can fall on any syllable, but no word ever has /e'o/ or /o'e/ (only /'eo/, /'oe/), then treating these sounds as diphthongs makes sense.